/*
 * Original Author -> Harry Yang (taketoday@foxmail.com) https://taketoday.cn
 * Copyright © TODAY & 2017 - 2021 All Rights Reserved.
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see [http://www.gnu.org/licenses/]
 */

package cn.taketoday.jdbc.dialect;

/**
 * @author TODAY 2021/10/10 13:12
 * @since 4.0
 */
public class OracleDialect extends Dialect {

  @Override
  public String pagination(SQLParams sqlParams) {
    PageRow pageRow = sqlParams.getPageRow();
    int limit = pageRow.getPageSize();
    int pageNum = pageRow.getPageNum();

    int start = (pageNum - 1) * limit + 1;
    int end = pageNum * limit;
    StringBuilder sql = new StringBuilder();
    sql.append("SELECT * FROM ( SELECT row_.*, rownum rownum_ FROM (  ");
    sql.append(select(sqlParams));
    sql.append(" ) row_ where rownum <= ").append(end).append(") table_alias");
    sql.append(" WHERE table_alias.rownum_ >= ").append(start);
    return sql.toString();
  }

}
